1. Field of the Invention
The present invention relates to a method and apparatus for subterranean support of underground conduits.
2. Description of the Related Art
Particularly in urban environments, when it is necessary to lay water or sewer pipe, construction crews will often encounter buried electrical, telephone, and/or fiber optic cables. These cables are typically encased in a clay tile or raceway that has a plurality of longitudinal holes through which the cables are pulled. In order to create a unitary subterranean support structure for the cables, individual raceway sections are placed end-to-end and mortared together. In order to lay water or sewer pipes, which must be buried below the freeze line, it is necessary to excavate beneath the raceway and the cables contained therein. However, when excavation occurs beneath the raceway, the raceway must be supported to prevent the raceway from collapsing into the excavated hole.
Currently, in order to support the raceway during and after excavation, the individual raceway tiles are jack hammered, causing the raceway tiles to break apart and expose the cables positioned therein. The exposed cables are then supported by one or more beams extending above the excavated hole. Once the water or sewer pipe is laid, the hole is backfilled and a concrete form is built around the cables. The form is filled with concrete and the concrete is allowed to harden. As a result, the cables are encased within the concrete and are protected from future damage. While this process is effective, it is also time consuming and expensive. Additionally, once the cables are encased in concrete, it is no longer possible to pull new cables through the raceway or to easily extract existing cables from the raceway.